Electrodes, lithium-ion batteries, and methods of making and using same
Described herein are improved composite anodes and lithium-ion batteries made therefrom. Further described are methods of making and using the improved anodes and batteries. In general, the anodes include a porous composite having a plurality of agglomerated nanocomposites. At least one of the plurality of agglomerated nanocomposites is formed from a dendritic particle, which is a three-dimensional, randomly-ordered assembly of nanoparticles of an electrically conducting material and a plurality of discrete non-porous nanoparticles of a non-carbon Group 4A element or mixture thereof disposed on a surface of the dendritic particle. At least one nanocomposite of the plurality of agglomerated nanocomposites has at least a portion of its dendritic particle in electrical communication with at least a portion of a dendritic particle of an adjacent nanocomposite in the plurality of agglomerated nanocomposites.
1. A porous composite comprising:
a plurality of agglomerated nanocomposites, wherein each of the plurality of nanocomposites comprises:
a dendritic particle comprising a three-dimensional, randomly-ordered assembly of nanoparticles of an electrically conducting material, and
a plurality of discrete non-porous nanoparticles of a non-carbon Group 4A element or mixture thereof disposed on a surface of the dendritic particle;
wherein each nanocomposite of the plurality of agglomerated nanocomposites has at least a portion of the dendritic particle in electrical communication with at least a portion of a dendritic particle of an adjacent nanocomposite in the plurality of agglomerated nanocomposites, and
wherein the porous composite comprises a total pore volume within the porous composite that has a range of 3 to 20 times the volume occupied by all of the non-carbon Group 4A element nanoparticles in the porous composite.
2. The porous composite of claim 1 , wherein the electrically conducting material of the dendritic particle is amorphous or graphitic carbon.
3. The porous composite of claim 2 , wherein the amorphous carbon is carbon black.
4. The porous composite of claim 1 , wherein the non-carbon Group 4A element or mixture thereof comprises silicon.
5. The porous composite of claim 1 , wherein the porous composite further comprises an electrically conducting coating disposed on at least a portion of a surface of a dendritic particle of at least one of the plurality of agglomerated nanocomposites.
6. The porous composite of claim 5 , wherein the electrically conducting coating is formed from carbon.
7. The porous composite of claim 1 , wherein the plurality of agglomerated nanocomposites are agglomerated together using an electrically conducting additive.
8. The porous composite of claim 7 , wherein the electrically conducting additive is carbon.
9. The porous composite of claim 1 , wherein the plurality of discrete non-porous nanoparticles has an average longest dimension of about 5 nanometers to about 200nanometers.
10. The porous composite of claim 1 , wherein the plurality of discrete non-porous nanoparticles comprise about 15 weight percent to about 90 weight percent of each nanocomposite.
11. The porous composite of claim 1 , wherein the porous composite is a spherical or substantially-spherical granule.
12. The porous composite of claim 1 , wherein at least a portion of the discrete non-porous nanoparticles on the surface of the dendritic particle contact each other.
13. A battery electrode comprising:
a conductive metal substrate; and
a porous composite dispersed in a binder coupled to the conductive metal substrate, wherein the porous composite comprises a plurality of agglomerated nanocomposites, wherein at least one nanocomposite of the plurality of agglomerated nanocomposites comprises:
a dendritic particle comprising a three-dimensional, randomly-ordered assembly of nanoparticles of an electrically conducting material, and
a plurality of discrete non-porous nanoparticles of a non-carbon Group 4A element disposed on a surface of the dendritic particle;
wherein the at least one nanocomposite of the plurality of agglomerated nanocomposites has at least a portion of the dendritic particle in electrical communication with at least a portion of a dendritic particle of an adjacent nanocomposite in the plurality of agglomerated nanocomposites, and
wherein the electrode comprises a total pore volume within the electrode that has a range of 3 to 20 times the volume occupied by all of the non-carbon Group 4A element nanoparticles in the porous composite.
14. A battery, comprising:
a cathode comprising lithium;
an anode comprising a porous composite dispersed in a binder coupled to a conductive metal substrate, wherein the porous composite comprises a plurality of agglomerated nanocomposites, wherein at least one of the plurality of nanocomposites comprises:
a dendritic particle comprising a three-dimensional, randomly-ordered assembly of nanoparticles of an electrically conducting material, and
a plurality of discrete non-porous nanoparticles of a non-carbon Group 4A element or mixture thereof disposed on a surface of the dendritic particle,
wherein at least one nanocomposite of the plurality of agglomerated nanocomposites has at least a portion of the dendritic particle in electrical communication with at least a portion of a dendritic particle of an adjacent nanocomposite in the plurality of agglomerated nanocomposites, and
wherein the anode comprises a total pore volume within the anode that has a range of 3 to 20 times the volume occupied by all of the non-carbon Group 4A element nanoparticles in the porous composite;
a separator, positioned between the cathode and the anode; and
an electrolyte composition disposed between the cathode and the anode.
15. A method of making a porous composite, the method comprising:
forming a plurality of agglomerated nanocomposites, wherein each of the plurality of nanocomposites is formed by:
obtaining a three-dimensional, randomly-ordered dendritic particle composed of a plurality of discrete nanoparticles of an electrically conducting material, and
disposing a plurality of discrete non-porous nanoparticles of a non-carbon Group 4A element or mixture thereof on a surface of the dendritic particle to form a nanocomposite particle;
wherein the porous composite is formed with a total pore volume within the porous composite that has a range of 3 to 20 times the volume occupied by all of the non-carbon Group 4A element nanoparticles in the porous composite.
16. The method of claim 15 , wherein the three-dimensional, randomly-ordered dendritic particle is obtained by annealing carbon black nanoparticles at a temperature of above about 2000 ° C.
17. The method of claim 15 , wherein the three-dimensional, randomly-ordered dendritic particle is obtained by pyrolysis of a hydrocarbon gas at a temperature of between about 700 ° C. to about 1400 ° C.
18. The method of claim 15 , wherein the plurality of discrete non-porous nanoparticles of a non-carbon Group 4A element or mixture thereof are disposed on the surface of the dendritic particle using a chemical vapor deposition process.
19. A method of making an electrode, the method comprising:
obtaining a porous composite, the porous composite comprising a plurality of agglomerated nanocomposites, wherein each of the plurality of nanocomposites comprises:
a dendritic particle comprising a three-dimensional, randomly-ordered assembly of nanoparticles of an electrically conducting material, and
a plurality of discrete non-porous nanoparticles of a non-carbon Group 4A element or mixture thereof disposed on a surface of the dendritic particle,
wherein each nanocomposite of the plurality of agglomerated nanocomposites has at least a portion of the dendritic particle in electrical communication with at least a portion of a dendritic particle of an adjacent nanocomposite in the plurality of agglomerated nanocomposites, and
wherein the electrode is formed with a total pore volume within the electrode that has a range of 3 to 20 times the volume occupied by all of the non-carbon Group 4A element nanoparticles in the porous composite;
forming a mixture of the porous composite with a binder; and
applying the mixture to a conductive metal substrate.